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In small-scale fisheries management, the significance of participation is widely recognised but we are still learning how this can be better operationalised to include different groups, such as women or Indigenous peoples. Participatory monitoring is one tool which has been used to increase participation in fisheries management. The aim of this review is to use critical interpretive synthesis to examine the literature on participatory monitoring within community-based fisheries management from a gender perspective. The synthesis identified and discussed several key areas: reasons presented in the literature for engaging with the themes of gender or participatory monitoring, gendered aspects of participatory monitoring, knowledge valuation and prioritisation in management, replicability and transparency of programme or research methods, and marginalisation narratives. Our findings show the complexities of conducting gender-aware participatory monitoring. Participatory monitoring has the potential to be a transformative and empowering process if the power dynamics involved are considered and addressed. [ABSTRACT FROM AUTHOR]

In this paper I examine the relationship of institutional structures of governance to the production, acceptance and legitimization of knowledge by various stakeholder groups participating in fisheries management arenas. I focus first on the New England groundfishery where the stock assessments of federal scientists have come under intense criticism by fishermen. As a counterpoint, I examine knowledge production for management purposes in two fisheries where cooperative management institutions have emerged: the Puget Sound region of Washington and the Kuskokwim River watershed of Alaska. Knowledge is produced and legitimated differently by the different stakeholders in the management process. The findings highlight the critical importance of two-way communication, in which stakeholder groups both listen and are listened to, in creating a legitimated and more robust knowledge base with which management decisions can be made. [ABSTRACT FROM AUTHOR]

This paper proposes a total fusion of blockchain and AI tech for tomorrow's viable, rich in diversity and transparent fisheries. It outlines the main goal of tackling overfishing challenges due to lack of transparency and biodiversity depletion in the fisheries sector. With the use of blockchain technology, we can ensure that all fishery products are safely traced from their harvest up to when they get to the market— at the same time, AI algorithms are used in monitoring fish populations and predicting them plus decision-making processes which should be enhanced thus promoting bio-diversity and ensuring sustainability of fish stocks. Results show promise on using both technologies together: improving sustainability plus transparency in fisheries which would promote more fish biodiversity, while others including using an artificial intelligence system have not been confirmed yet by observations. The conclusion underscores the transformative nature of these technologies as having great implications towards fisheries management; this implies that there is a need for future observational studies aimed at validating such other findings. [ABSTRACT FROM AUTHOR]

Underwater segmentation technology achieves effective monitoring of fish biological information through accurate identification of fish species and precise estimation of their quantities. It serves as an effective approach to enhance the informatization level of aquaculture and promote intelligent management in fisheries. However, the complex and diverse underwater environment, coupled with poor visibility, results in blurry and lower-quality underwater fish images. The current image segmentation methods, when applied to fish segmentation, exhibit low accuracy and inadequate generalization capabilities. This paper proposes an image segmentation model based on Atrous Spatial Pyramid Pooling (ASPP) to address these challenges. The model aims to improve fish feature extraction and enhance the segmentation precision of fish images in complex underwater environments, thereby enhancing the accuracy and generalization capabilities of existing fish segmentation models. First, a multiscale feature extraction module (triangular atrous spatial pyramid multifeature fusion) based on dilated convolutional spatial pyramid pooling, which enhances the extraction of high-level semantic features of images through the triangular combination of multilayer dilated convolutional pyramid pooling and the adaptive channel attention module, is proposed. Second, a spatial attention module based on strip pooling (atrous strip pooling) is proposed, which further expands the receptive field of the attention mechanism by combining different expansion rates, enhances the correlations between pixels, and effectively captures spatial information. Finally, a decoder module based on multilayer semantic feature fusion is proposed. Through the processing and fusion of medium-, low-, and high-level semantic features, the model understands image content and performs accurate pixel-level segmentation. The proposed model is evaluated using a VOC-compliant dataset created from underwater fish images and validated against public and specific underwater fish datasets. The results demonstrate the successful application of the feature extraction and feature fusion modules in underwater fish image segmentation, achieving an average Intersection over Union (MIoU) of 85.49% in segmentation tasks. Compared to conventional segmentation models, the proposed model shows significant improvements, with an average increase of 3.8% in MIoU and 2.5% in balanced F-score (F1-score). The accurate segmentation of underwater fish images and extraction of vital biological information by this model provide a solid foundation for intelligent monitoring, including fish length measurement, weight estimation, and analysis of growth and health status. Moreover, the model offers a scientific framework for decision-making in aquaculture, driving advancements in precision and intelligent management practices in the field. [ABSTRACT FROM AUTHOR]

The intensive utilization of tropical inland water bodies for multiple and sometimes competing activities underlines the necessity for their integrated and holistic co-management. This paper presents our synthesis on lake and reservoir fisheries in South and Southeast Asia as social–ecological systems, based on a synopsis of our research findings from a previous EU-funded research programme in Sri Lanka, Thailand and the Philippines (FISHSTRAT project). The paper attempts to merge our results with recent developments in research, policy and practice. We explore the effects of the main external and internal control mechanisms of the trophic state and pinpoint to the high production potential of traditionally unexploited small indigenous fish species. The limitations of conventional centralized management systems highlight the importance of introducing transdisciplinary approaches which integrate limnology, fish ecology and fisheries with the interests of other resource using stakeholders and decision makers in order to develop locally appropriate co-management strategies for sustainable aquatic resource use. [ABSTRACT FROM AUTHOR]

Marine megafauna are critical for marine ecosystem health and their removal can cause food webs to collapse. Methods to reduce marine megafauna mortality can result in conflict between scientists, conservationists, fishers and fisheries management due to real or perceived effects on target catch, income and food security. Sensory deterrents have been used in attempts to mitigate bycatch and retain target catch quantity and quality. Here, we completed a systematic review of 116 papers, plus 25 literature reviews published between 1991 and 2022, to investigate potential for sensory deterrents to mitigate bycatch across four marine megafauna taxonomic groups (marine mammals, sea turtles, seabirds and elasmobranchs). Lights on gillnets are the only technology so far to result in significant bycatch reductions across all four taxonomic groups. It is difficult to make generalisations about the efficacy of sensory deterrents and their ability to deliver consistent bycatch reductions. The efficacy of each method is context dependent, varying with species, fishery and environmental characteristics. Further research is recommended for field studies assessing bycatch mitigation in all sensory deterrents, including combinations of deterrents, to assess effects on target and non-target species. The associated issues of habituation, habitat exclusion and foraging around fishing gear are important, although reducing mortality of vulnerable species should remain the highest priority for conservation and preserving ecosystems that fishers depend on. Multiple complementary measures will be required to achieve consistent bycatch reduction targets in many fisheries, of which sensory deterrents could play some part if implemented appropriately. [ABSTRACT FROM AUTHOR]

In the 1950s, the Soviet Union expanded the range of its fisheries operations into international water traditionally fished by American vessels. In the USA, government officials and fisheries experts alike expressed concerns that the Soviets were overfishing Atlantic stocks, or even potentially engaging in off-shore espionage. Despite these fears, members of the US fisheries management community reached out and engaged with their Soviet counterparts directly. This initial communication led to a series of collaborations between US and Soviet scientific agencies aimed at developing a deeper understanding of marine ecosystems and improving the sustainability of international fisheries. The joint US–USSR research efforts beginning in the 1960s laid the foundation for continued cooperative studies through the 1980s and into the post-Soviet era. This paper uses historical records from the US National Archives and data products currently available on the web to examine the legacy of this Cold War cooperative research program. These materials demonstrate how American and Soviet scientists collaborated to generate and describe data on fisheries. It also considers how they negotiated recordkeeping and data management activities across radically different governmental structures, while also navigating the transition to digital recordkeeping and data exchange. This case offers perspective on the preservation of at-risk ecological records and the continued value of these data in our contemporary world. [ABSTRACT FROM AUTHOR]

Evaluation of fish stock status is a key step for fisheries management. Tuna Regional Fisheries Management Organizations (t-RFMOs) are moving towards management strategy evaluation (MSE), a process that combines science and policy and depends on technical aspects, developed by scientists, designed to meet management objectives established by managers and other stakeholders. In the Indian Ocean, the current management advice for swordfish (Xiphias gladius) is based on an ensemble of 24 models considering four areas of uncertainty about the stock dynamics. There is an ongoing MSE process for swordfish, and this paper describes the methodology being applied for the conditioning of the operating model (OM), including model selection and validation. In the MSE, nine sources of uncertainty were considered, each being characterized by 2–3 levels. A partial factorial design was employed to reduce the number of models from a full factorial design to those needed to encompass the overall uncertainty. A selection and validation process was carried out, filtering models that converged, showed good predictive skills, and provided plausible estimates. Overall, the estimated spawning stock biomass (SSB) relative to SSB at maximum sustainable yield (MSY), and fishing mortality (F) relative to FMSY encompasses the estimates of the stock assessment ensemble at the most optimist area of the distribution. The MSE for swordfish is an ongoing process that is expected to provide more robust management advice in the future. Further developments to the OM can still occur, but the methods presented herein can be applied to this, or other species, MSE processes. [ABSTRACT FROM AUTHOR]

The Commission for the Convention on the Conservation of Antarctic Marine Living Resources is the body responsible for the conservation and management of most species in the Southern Ocean. The Convention mandates that decisions be made by consensus agreement of its Members. This approach has been largely successful in delivering strong management decisions across both complex issues and widely ranging national interests. However, recent failures to progress the implementation of a network of marine protected areas or to agree any concrete response actions to climate impacts raise concerns about its effectiveness. This paper reviews the level of uptake of Member-driven proposals and then examines examples of proposals that were not resolved within the usual three years to analyse the processes utilised by Members to find resolution. It concludes that CCAMLR has been successful in reaching agreements when focusing on fisheries management but less so on issues within its broader conservation mandate, such as area protection for biodiversity purposes or non-fishery management focused scientific study, or for issues that are perceiv ed to extend the competency of the Convention. It notes that CCAMLR lacks operational mechanisms to facilitate agreement in the absence of compromise text or when one or two Members cannot accept a proposal. [ABSTRACT FROM AUTHOR]

In 2015, the international community adopted the United Nations Sustainable Development Goals (SDGs), a goal-setting governance strategy that aims to achieve sustainable development across social, economic, and ecological areas. SDG 14 ('life below water') is directed to the sustainable use and conservation of the oceans and marine resources. Regional fisheries management organizations (RFMOs) are key institutions in managing international fisheries and thus have the potential to play a significant role in realizing the attainment of SDG 14. This paper aims to assess how RFMOs could contribute to SDG 14 by examining their treaty texts and implementation of conservation and management measures or collaborative networks. The results of this paper highlights the contribution of RFMOs to targets such as ending overfishing and indicates the need for further attention towards area protection. The findings of the network assessment show that RFMOs mainly cooperate with other RFMOs or fisheries-related organizations, indicating a lack of cooperation with other maritime organizations. Moreover, the objective of most of these collaborations is sharing of information or data, while actions against problems such as the bycatch of non-target species are missing. Thus, this paper highlights how existing regional organizations have the potential to increase their contribution to SDG 14, by aligning more of their work to this goal. To support this process, we developed a list of considerations and actions. [ABSTRACT FROM AUTHOR]

Fisheries in the East China Sea (ECS) face multiple concerning trends. Aside from depleted stocks caused by overfishing, illegal encroachments by fishermen from one nation into another's legal waters are a common occurrence. This behavior presumably could be stopped via strong monitoring, controls, and surveillance (MCS), but MCS is routinely rated as below standards for nations bordering the ECS. This paper generalizes the ECS to a model of a congested maritime environment, defined as an environment where multiple nations can fish in the same waters with equivalent operating costs, and uses game-theoretic analysis to explain why the observed behavior persists in the ECS. The paper finds that nations in congested environments are incentivized to issue excessive quotas, which in turn tacitly encourages illegal fishing and extracts illegal rent from another's legal waters. This behavior couldn't persist in the face of strong MCS measures, and states are thus likewise incentivized to use poor MCS. A bargaining problem is analyzed to complement the noncooperative game, and a key finding is the nation with lower nonoperating costs has great leverage during the bargain. [ABSTRACT FROM AUTHOR]

In many countries, commercial and recreational fishing compete for access to marine resources. In some cases, recreational catch outweighs commercial harvest and may threaten species otherwise protected from commercial fishing. This has led to increasing calls for improved management of recreational fishing in the broader context of general fisheries management. As a result, fisheries managers face the challenge to decide how to allocate the available marine resources between competing uses. In this paper, we review and explain two common approaches that have been used to support recreational fishing allocation decisions. While economic activity analysis is an appropriate tool to assess how a change in resource allocation would affect regional economic activity (economic contributions and impacts), it is ill-suited to assess associated gains or losses in welfare of society as a whole (economic efficiency). Hence, economic activity analysis and social cost–benefit analysis complement each other, with each providing a different set of information answering a different set of questions. Unfortunately, both types of analysis use the term "economic value" suggesting that they are alternative approaches that provide the same information, whereas in fact they are not. If the objective of fishery managers is to ensure that society as a whole is made better off, the appropriate metric is economic value as defined by welfare economics. Under this definition, all goods and services provided by marine resources that are beneficial to humans have economic value. This includes non-use values such as the continued existence of an endangered marine species. The aim of this paper is to support managers and policymakers in allocating marine resources by reviewing relevant economic principles, concepts, and tools in the context of recreational fishing, including the use and challenges of estimating the non-market benefits generated by recreational fishing experiences. [ABSTRACT FROM AUTHOR]

Climate change impacts on fishery resources have been widely reported worldwide. Nevertheless, a knowledge gap remains for the warm-temperate Southwest Atlantic Ocean—a global warming hotspot that sustains important industrial and small-scale fisheries. By combining a trait-based framework and long-term landing records, we assessed species' sensitivity to climate change and potential changes in the distribution of important fishery resources (n = 28; i.e., bony fishes, chondrichthyans, crustaceans, and mollusks) in Southern Brazil, Uruguay, and the northern shelf of Argentina. Most species showed moderate or high sensitivity, with mollusks (e.g., sedentary bivalves and snails) being the group with the highest sensitivity, followed by chondrichthyans. Bony fishes showed low and moderate sensitivities, while crustacean sensitivities were species-specific. The stock and/or conservation status overall contributed the most to higher sensitivity. Between 1989 and 2019, species with low and moderate sensitivity dominated regional landings, regardless of the jurisdiction analyzed. A considerable fraction of these landings consisted of species scoring high or very high on an indicator for potential to change their current distribution. These results suggest that although the bulk of past landings were from relatively climate-resilient species, future catches and even entire benthic fisheries may be jeopardized because (1) some exploited species showed high or very high sensitivities and (2) the increase in the relative representation of landings in species whose distribution may change. This paper provides novel results and insights relevant for fisheries management from a region where the effects of climate change have been overlooked, and which lacks a coordinated governance system for climate-resilient fisheries. [ABSTRACT FROM AUTHOR]

There are many syntheses on the role of animal behavior in understanding and mitigating conservation threats for wildlife. That body of work has inspired the development of a new discipline called conservation behavior. Yet, the majority of those synthetic papers focus on non-fish taxa such as birds and mammals. Many fish populations are subject to intensive exploitation and management and for decades researchers have used concepts and knowledge from animal behavior to support management and conservation actions. Dr. David L. G. Noakes is an influential ethologist who did much foundational work related to illustrating how behavior was relevant to the management and conservation of wild fish. We pay tribute to the late Dr. Noakes by summarizing the relevance of animal behavior to fisheries management and conservation. To do so, we first consider what behavior has revealed about how fish respond to key threats such as habitat alteration and loss, invasive species, climate change, pollution, and exploitation. We then consider how behavior has informed the application of common management interventions such as protected areas and spatial planning, stock enhancement, and restoration of habitat and connectivity. Our synthesis focuses on the totality of the field but includes reflections on the specific contributions of Dr. Noakes. Themes emerging from his approach include the value of fundamental research, management-scale experiments, and bridging behavior, physiology, and ecology. Animal behavior plays a key role in understanding and mitigating threats to wild fish populations and will become more important with the increasing pressures facing aquatic ecosystems. Fortunately, the toolbox for studying behavior is expanding, with technological and analytical advances revolutionizing our understanding of wild fish and generating new knowledge for fisheries managers and conservation practitioners. [ABSTRACT FROM AUTHOR]

Purpose: Although life cycle impact assessment methods exist for quantifying land use and its impact on the environment in the "ecosystem quality" area of protection, the impact of sea use on ecosystems has been poorly assessed so far. This paper aims to propose operational characterisation factors for all global fisheries. Methods: For a given intervention, the characterisation factor is defined as the product of the fate factor (inverse of the fish stock growth rate) and the effect factor (depleted fraction of the stock). Characterisation factors are provided for 5000 fish stocks identified by the Food and Agriculture Organization. Both the marginal and average approaches are used, and characterisation factors compatible with the ReCiPe method and the international guidelines of the Life Cycle Initiative hosted by the UN Environment Programme are proposed. Results and discussion: Characterisation factors for regional and global assessments can be employed to address the endemic nature of a species. As an illustration, four contrasting fisheries are presented and compared with land animal production systems. Impacts varied between stocks and between regional and global assessment, particularly with highly endemic species exhibiting impacts comparable to or exceeding land-based animal products. Conclusions: Although in some cases associated uncertainty is large, the proposed method allows endpoint characterisation, in line with the ReCiPe methodology and Life Cycle Initiative, contributing the assessment of fishing impacts on ecosystem quality and a more holistic representation in food impact assessment. [ABSTRACT FROM AUTHOR]

Multispecies bio-economic models are useful tools to give insights into ecosystem thinking and ecosystem-based management. This paper developed an age-structured multispecies bio-economic model that includes the food web relations of the grey seal, salmon, and herring, along with salmon and herring fisheries in the Baltic Sea. The results show that the increasing seal population influences salmon fisheries and stock, but the impacts on the harvest are stronger than on the stock if the targeted management policies are obeyed. If seal population growth and a low herring stock occur simultaneously, the salmon harvest could face a serious threat. In addition, scenarios of the multispecies management approach in this paper reveal a benefit that our model can evaluate the performance of different fisheries with identical or different management strategies simultaneously. The results show the most profitable scenario is that both fisheries pursuit aggregated profits and reveal a trade-off between herring fisheries and salmon fisheries. Our model indicates that the herring harvest level and the approaches to managing herring fisheries can influence the performance of salmon fisheries. The study also demonstrates a way to develop a multispecies bio-economic model that includes both migratory fish and mammalian predators. [ABSTRACT FROM AUTHOR]

In the Global South, small-scale fisheries may be highly influenced by taboos and traditional beliefs that are believed to maintain fishing pressure within sustainable limits, maintain ecosystem balance and mitigate risks associated with work at sea. However, despite their potentially significant role in mediating human-resource interactions, limited attention has been given to taboos in the context of small-scale fisheries. Among the socio-cultural taboos shaping participation in and benefits from fisheries activities, gender-specific taboos are particularly significant. Thus, this paper explores the role of gender taboos in sustainable and equitable small-scale fisheries management in the Global South. It also identifies and assesses the quality and scientific rigor of the key themes from the literature. A systematic literature review was conducted to assess the state of knowledge on taboos and small-scale fisheries and situate the role of gender-specific taboos within small-scale fisheries governance. Over 100 relevant publications were obtained and categorised using scanning and selection methods. The main emerging themes from the literature review included traditional ecological knowledge and taboos, conservation and management taboos, and gender taboos. The findings highlight the significance of taboos in shaping gender dynamics, livelihoods, and food security within small-scale fisheries; however, there remain many gaps in understanding the role of taboos in mediating fishing activities and in maintaining gender inequalities in the fisheries sector. Without this knowledge, gender inequalities could be further exacerbated where taboos are used as a management tool without considering the gender dimensions. This study, therefore, seeks to fill this gap by providing insights for fisheries managers and practitioners for managing fisheries in a way that considers these socio-cultural factors that shape access to, control over and the benefits derived from fisheries. [ABSTRACT FROM AUTHOR]

In this paper we model spatio-temporal data describing the fishing activities in the Northern Adriatic Sea over four years. We build, implement and analyze a database based on the fusion of two complementary data sources: trajectories from fishing vessels (obtained from terrestrial Automatic Identification System, or AIS, data feed) and fish catch reports (i.e., the quantity and type of fish caught) of the main fishing market of the area. We present all the phases of the database creation, starting from the raw data and proceeding through data exploration, data cleaning, trajectory reconstruction and semantic enrichment. We implement the database by using MobilityDB, an open source geospatial trajectory data management and analysis platform. Subsequently, we perform various analyses on the resulting spatio-temporal database, with the goal of mapping the fishing activities on some key species, highlighting all the interesting information and inferring new knowledge that will be useful for fishery management. Furthermore, we investigate the use of machine learning methods for predicting the Catch Per Unit Effort (CPUE), an indicator of the fishing resources exploitation in order to drive specific policy design. A variety of prediction methods, taking as input the data in the database and environmental factors such as sea temperature, waves height and Clorophill-a, are put at work in order to assess their prediction ability in this field. To the best of our knowledge, our work represents the first attempt to integrate fishing ships trajectories derived from AIS data, environmental data and catch data for spatio-temporal prediction of CPUE – a challenging task. [ABSTRACT FROM AUTHOR]

As part of an interdisciplinary research project on South Pacific fisheries, we recognized children as one of the relevant categories of stakeholders whose perspectives on fishing and fisheries management need to be considered. We used drawings to explore how, in Fiji and New Caledonia, children perceive their marine environment, including the fishing practices and the connections between these and local ways of 'being-in-the-world.' Our methodology involved drawing workshops in local schools, followed by short interviews with the participants. This methodological paper aims to identify the advantages and limitations of this drawing-based approach to research with children compared to conventional ethnographic and ethnoecological methods. Therefore, it focuses primarily on how this approach was designed and implemented and on the epistemological discussions it generated, especially concerning children's involvement in the study and the use of drawing as a research tool. [ABSTRACT FROM AUTHOR]

In this paper, a sustainability framework with a case application for UK's Scottish fisheries has been developed which integrates aspects related to economic growth, social development, governance, biology, environment, and logistics. Scotland is the centre of UK's commercial fishery sector however it faces challenges such as overexploitation, and changes in the governance structure following Brexit. The contributions of this study are threefold including (i) collecting and analysing primary data gathered from a diverse group of stakeholders in the Scottish fishery sector and scientific community, (ii) prioritising a diverse range of criteria in terms of importance in decision making from industry and scientific community perspectives, (iii) elaboration of the key management objectives in this region within the context of sustainable management of fisheries in the UK. The results of this stakeholders' survey show that the key management objectives are reductions in overexploitation of stocks, inclusive governance, increase in transparency and simplicity of policy measures, reduction in marine litter, and increase in the efficiency of vessels. The analysis also shows that the industry group places a higher importance on socio-economic objectives such as increase in profit and employment compared to the scientific group. On the other hand, the scientific group prioritised the objectives such as reducing discards, bycatch, and impact on seafloor compared to the industry group. This study provides insight for the UK's fisheries sector, and scientific advisory groups for the enhanced implementation of sustainable fisheries management policies. [ABSTRACT FROM AUTHOR]

This paper develops a model based on the concept of Positive Mathematical Programming (PMP) that is useful for ex-ante analyses of how policy measures affect commercial fisheries. PMP models are frequently used in agriculture, but rarely for analyzing fisheries. Fisheries often face a large set of constraints such as effort regulations and catch quotas of which some might be binding and others not. An econometric approach is developed for calibrating models with both binding and non-binding constraints. The interaction between seals and Swedish fisheries is used as an empirical application. Seal interaction is modeled as seals predating fish from passive gear (nets and hooks), which is primarily an issue for the coastal fishery. The model contains 24 fleet segments involved in 247 different fishing activities in 2012. The results show that if no further management action is taken, fisheries using passive gear will reduce their activities from about 46 000 days at sea per year to about 41 000 and reducing their economic performance from losses of about 2 million Euros to about 3.3 million. The impact from seals can be reduced by reducing the seal population or providing economic compensation. [ABSTRACT FROM AUTHOR]

This paper contributes to the growing body of literature that engages with ontological scholarship on fisheries management and governance, and more generally, to debates on environmental governance. It argues that fisheries governance is an ontological challenge that raises questions of culture, equity, legitimacy and inclusion/exclusion, requiring more context-sensitive and politically aware fisheries governance approaches. By engaging with the concept of political ontology, and drawing from empirical research carried out in Ireland's offshore islands, five ontological assumptions are identified that underpin Irish fisheries governance and management policies and practices and categorised as social-historical, ecological, geographical, technocratic and markets-driven. Articulating and examining these assumptions provide insights into why policy objectives aimed at supporting small-scale fisheries and their communities may, in practice, not be effective when they are operationalised within a governance paradigm designed around the realities of large-scale, full-time, highly mobile and more economically productive operators. Despite the efforts of ontologically disobedient islanders, the enactment of these ontological assumptions into the dominant world of fisheries governance inhibits the emergence of possible worlds that would enact Irish island inshore fisheries through island logics. The paper concludes that the squeeze on Ireland's island inshore fishers is not simply spatial, it is ontological. A dominant fisheries ontology has been created by the interplay of ontological assumptions. This dominant ontology undermines the State's critical policy to maintain and manage Irish fisheries as a public resource in order to avoid the concentration of fishing opportunities into the hands of large and powerful fishing interests. [ABSTRACT FROM AUTHOR]

This paper analyses sustainability of bilateral harvesting agreements in transboundary fisheries. Harvesting countries obtain public and private assessments regarding their stock of fish, and the stock experiences ecological changes. In addition to biological uncertainty, countries may face strategic uncertainty. A country that receives negative assessments about the current level of fish stock, may become 'pessimistic' about the assessment of the other coastal state, and this can ignite 'panic-based' overfishing. The paper examines the likelihood of overfishing and suggests a unique prediction about the possibility of abiding by bilateral fishing agreements. Conditions under which the outcome of the asymmetric-information model reduces to the symmetric-information game are discussed, and optimal policy instruments for intergovernmental management of the stock are offered. [ABSTRACT FROM AUTHOR]

High demand and prices in global markets for luxury seafood fished by coastal communities in low-income contexts causes overfishing. There are few alternatives for fishers to earn money, most institutions for controlling effort are weak, and markets are beyond the control of fishing states. The mismatch between desires for development and governance measures to enable that development is shared across many high-value low-income contexts. Using the sea cucumber fishery of Papua New Guinea as an example, this paper illustrates how the interactive governance framework provides a holistic approach to revealing governability limits and opportunities. Analysis of the system to be governed demonstrates that development for coastal communities is fundamental to the fishery as a motivating force and as a principle legitimising actions within the fishery and its management. This analysis highlights the fact that fisheries management is based on the assumption that an open fishery will lead to development, due to its economic value. However, money does not equal development. For this and other similar fisheries to increase development in coastal communities, issues not usually considered within the purview of the management of fisheries must be addressed, including gendered and intergenerational decision-making and income distribution, financial planning and government provision of infrastructure and services. [ABSTRACT FROM AUTHOR]

Over the last three decades most of the world's fisheries have been subject to management programs that have tried to limit the use of key fishing inputs. Inevitably, these restrictions have proven ineffective at preventing rent dissipation and stock depletion. More noteworthy is that fishers have subverted the intentions of these restrictions by adjusting the primary harvesting technology. This has led to an inefficient industrial structure characterized by capital stuffing on the part of each vessel, excess employment, an inefficient mix of vessels in the fleet, and too many vessels altogether. A promising means of encouraging more efficient primary harvesting is the individual transferable vessel quota that allocates a given catch to each vessel, thereby giving an incentive to catch the quota at least cost. This paper examines efficiency gains and potential industry restructuring from the introduction of an ITVQ into a fishery that was previously subject to input restrictions. Using data from the British Columbia salmon fishery, this paper estimates restricted cost functions for each of four different vessel types and simulates the operations of a market for ITVQs. The demand for quota comes from individual vessels and is found by differentiating the cost function with respect to the shadow price of quota. The market for quota is in equilibrium when the total demand for quota is equal to the fixed supply of quota set by the government. This implicitly defines the equilibrium quota rental price. Results show that the ITVQ could generate unit rental prices for quota between 31 and 93 cents per pound (18–53% of the average landed price). Using this simulated price, each vessel's cost-minimizing strategy is defined and both low cost vessels (those that will buy quota) and high cost vessels (those that will sell quota and exit the fishery) are identified. Quota trades between the two groups result in efficiency gains. These include reduced capital stuffing, exit of less efficient vessel types, attainment of economies of scale, and an efficient composition of vessel types in the fleet. In aggregate these gains lead to an estimate of annual resource rent that is approximately equal to one third of the value of the catch. [ABSTRACT FROM AUTHOR]

The giant jellyfish Nemopilema nomurai is the largest and most dangerous jellyfish species in East Asian waters, and the N. nomurai bloom causes serious problem in coastal industries, fisheries, and tourism. In the previous surveys, we found N. nomurai could not be observed in the south of 30°N. In this paper, we analyzed the mechanism of this phenomenon. After exploring the possible impacts of different environmental factors, we found that physical processes are essential to the distribution pattern of N. nomurai rather than biological or chemical factors in the East China Sea. The combination of the location of the initial breeding places of N. nomurai and the current system determine the distribution pattern. This study could provide important insights to the potential control of the giant jellyfish in the Chinese coastal waters. [ABSTRACT FROM AUTHOR]

Visible spectral radiometric measurements from space, commonly referred to as ocean-colour measurements, provide a rich stream of information on ocean biota as well as on biological and ecosystem processes. The strength of the ocean-colour technology for observing marine life lies in its global reach, combined with its ability to sample the field at a variety of spatial and temporal scales that match the scales of the processes themselves. Another advantage lies in the growing length of the time series of ocean-colour-derived products, enabiling investigations into any long-term changes, if present. This paper presents an overview of the principles and applications of ocean-colour data. The concentration of chlorophyll-a, the major pigment present in phytoplankton–single-celled, free-floating plants that are present in the sunlit layers of the ocean–was the first, and remains the most common, biological variable derived from ocean-colour data. Over the years, the list of ocean-colour products have grown to encompass many measures of the marine ecosystem and its functions, including primary production, phenology and ecosystem structure. Applications that exploit the data are many and varied, and include ecosystem-based fisheries management, biogeochemical cycles in the ocean, ecosystem health and climate change. An integrated approach, incorporating other modes of ocean observations and models with satellite observations, is needed to investigate the mysteries of the marine ecosystem. [ABSTRACT FROM AUTHOR]

Bycatch continues to be a challenge to sustainable fisheries management (The term "bycatch" in this paper covers discards and does not include retained incidental catch). Bycatch estimates can inform stock status determinations by improving understanding of fishing mortality, and help managers monitor the effectiveness of regulations. Assessments of the quality of bycatch estimation programs and procedures are necessary to evaluate the precision and limitations of their results over time. NOAA Fisheries experts used a "Tier Classification System" (TCS) to compare the quality of fish bycatch data and estimation methods for U.S. commercial fisheries in 2005 and 2015. The TCS included criteria related to data adequacy and analytical approaches. A comparison of U.S. fishery tier scores demonstrated that most fisheries were classified into higher tiers in 2015 compared to 2005 due to factors including improved sampling design. In addition, this comparison identified region-specific trends (e.g., mostly improvements occurred for Alaska fisheries with more mixed results for Greater Atlantic fisheries). The improvements in bycatch data quality and estimation methods in the United States are a result of financial investments in observer programs by NOAA Fisheries and industry partners, as well as effective conservation measures implemented by regional fishery management councils and NOAA Fisheries. The TCS was also used to assess bycatch data and estimation methods in all of Australia's fishery jurisdictions for the decade 2010–19, illustrating the international applicability of the method. Overall, Australian state fisheries scored lower than federally managed fisheries in both the United States and Australia, reflecting the fact that the latter fisheries tend to be larger (and more valuable) than those in state jurisdictions, with a larger investment in observer programs. A comparison of tier scores and estimates of discards by fishery may provide a useful input for decision-making processes regarding allocation of resources to improve bycatch monitoring. [ABSTRACT FROM AUTHOR]

With gradual decline of global finfish resources, fisheries targeting cephalopods expanded. Yet, the stock assessment and management practice are frequently lacking, and existing ones often remain poorly suited for cephalopod unique life-history. In light of increasing ecological disturbances in marine ecosystems worldwide, assessing exploited species' status and response becomes vital for devising effective strategies that would ensure their sustainable management. There is generally scarce understanding of the way fisheries and other environmental stressors exert their combined effects on cephalopods stock dynamic and long-term resilience. To that end, evolutionary-based population studies that inform on identity, connectivity and adaptive potential of natural populations present a unique opportunity for assessing the viability of exploited cephalopod stocks. Such studies have been revolutionized in the last decade by proliferation of next generation sequencing technologies. They offer new avenues for expanding our knowledge, especially on population structure and the evolutionary responses to shifts in environmental pressures. In this paper we elaborate on how deep genomic insights into demographic and evolutionary status of fished cephalopods could improve their stock assessment and management practice. We also propose that the common octopus Octopus vulgaris would be a suitable model species to test the power of evolutionary tools to inform fishery scientists and managers on biological questions relevant for their sustainable exploitation. [ABSTRACT FROM AUTHOR]

Bycatch remains one of the most significant fisheries issues in the world and its monitoring and reporting is now expected in many regions. This paper provides a global synthesis of the data that are available on one of the most controversial components of bycatch, that associated with the capture and discarding of endangered, threatened and protected (ETP) species in marine commercial and artisanal fisheries. We examine the available literature regarding estimates for the key taxa in this category of bycatch (seabirds, turtles, sea snakes, marine mammals, sharks, rays and teleosts) and use the data to try to provide a total global estimate. We estimate (albeit quite imprecisely) that at least 20 million individuals of such species are discarded annually throughout the world. However, there remain far too many gaps and uncertainties across fisheries and regions in the information to provide any robustness (or variance) around such an estimate, nor to determine the actual fates of these animals (many may survive). This is exacerbated because: (1) the occurrences of such species are often rare and controversial and so go either unnoticed and/or unrecorded; (2) different levels of protection are afforded to different ETP species in different countries and fisheries and; (3) discarding practices vary greatly across a hierarchy of spatio-temporal scales and according to individual fishing conditions and procedures—the latter affecting actual mortalities. Nevertheless, there have been major initiatives established in recent years to provide better data on such interactions in addition to novel fishing methods and practices that reduce them and also improve the survival of discarded individuals. This paper discusses the data currently available and the quite significant gaps that remain. [ABSTRACT FROM AUTHOR]

This paper details the process of bottom-up crafting of by-laws to the state fishery laws in Zambia, the initial empirical case informing the development of the constitutionality concept. It explores the historical, political as well as environmental and economic conditions on which the process of sense of ownership of the institution building process came to be. The role of the researchers as well as the process of crafting new rules in a situation of an absent state but which is ideologically present as the owner of the resource are discussed. Furthermore, we underline that for this process the issue of bargaining power in communities that are very heterogeneous is a major challenge to a fair process for the crafting of institutions. The paper explains the main factors leading to what Haller et al. have labeled “constitutionality” addressing these power disparities. However, a clear examination of the process of the by-law crafting, including the content of the by-laws themselves, reveals that newly crafted institutions developed by local actors a) go beyond pure resource governance issues to include other areas related to fisheries (health and sanitation), b) address vital gender and power relations, and c) show high innovation potential to interrelate governance issues that are locally important but not addressed in fragmented state governance. [ABSTRACT FROM AUTHOR]

Oceanic frontal zones have been shown to deeply influence the distribution of primary producers and, at the other extreme of the trophic web, top predators. However, the relationship between these structures and intermediate trophic levels is much more obscure. In this paper we address this knowledge gap by comparing acoustic measurements of mesopelagic fish concentrations to satellite-derived fine-scale Lagrangian Coherent Structures in the Indian sector of the Southern Ocean. First, we demonstrate that higher fish concentrations occur more frequently in correspondence with strong Lagrangian Coherent Structures. Secondly, we illustrate that, while increased fish densities are more likely to be observed over these structures, the presence of a fine-scale feature does not imply a concomitant fish accumulation, as other factors affect fish distribution. Thirdly, we show that, when only chlorophyll-rich waters are considered, front intensity modulates significantly more the local fish concentration. Finally, we discuss a model representing fish movement along Lagrangian features, specifically built for mid-trophic levels. Its results, obtained with realistic parameters, are qualitatively consistent with the observations and the spatio-temporal scales analysed. Overall, these findings may help to integrate intermediate trophic levels in trophic models, which can ultimately support management and conservation policies. [ABSTRACT FROM AUTHOR]

Technology that is developed for or adopted by the recreational fisheries sector (e.g., anglers and the recreational fishing industry) has led to rapid and dramatic changes in how recreational anglers interact with fisheries resources. From improvements in finding and catching fish to emulating their natural prey and accessing previously inaccessible waters, to anglers sharing their exploits with others, technology is completely changing all aspects of recreational fishing. These innovations would superficially be viewed as positive from the perspective of the angler (aside from the financial cost of purchasing some technologies), yet for the fisheries manager and policy maker, technology may create unintended challenges that lead to reactionary or even ill-defined approaches as they attempt to keep up with these changes. The goal of this paper is to consider how innovations in recreational fishing are changing the way that anglers interact with fish, and thus how recreational fisheries management is undertaken. We use a combination of structured reviews and expert analyses combined with descriptive case studies to highlight the many ways that technology is influencing recreational fishing practice, and, relatedly, what it means for changing how fisheries and/or these technologies need to be managed—from changes in fish capture, to fish handling, to how anglers share information with each other and with managers. Given that technology is continually evolving, we hope that the examples provided here lead to more and better monitoring of technological innovations and engagement by the management and policy authorities with the recreational fishing sector. Doing so will ensure that management actions related to emerging and evolving recreational fishing technology are more proactive than reactive. [ABSTRACT FROM AUTHOR]

Global marine capture fisheries are undergoing serious stress, with overfishing as one of the major problems. In order to mitigate the overexploitation of capture fisheries, government regulation or fisheries management is necessary. Among various management approaches, vessel quantity control is being widely employed. To achieve effective governance of fisheries, the technical efficiency (TE) issue needs to be considered in the implementation of vessel quantity control. Using the Pacific saury ( Cololabis saira) stick-held dip net fishery in Japan as a case study, this paper estimated the TE of sampled fishing vessels and explored the possible factors affecting the gap in efficiency. This paper aims to provide suggestions for a better implementation of vessel quantity control in global Pacific saury fishery, and also to serve as an empirical example of integrating TE analysis into management of overexploited fisheries for achieving satisfactory effects. Results show the TE score of the sampled fishery averaged around 0.7 from 2009 to 2014, and factors concerning owners/skippers' motivation such as vessel ownership and specialization, vessel tonnage as well as skippers' age show positive effects on the TE. Our findings in the present work provide important strategies for mitigating overexploitation in fisheries. Conducting technical efficiency analysis of targeted fisheries is a vital issue to be considered for designing and realizing an effective implementation of fisheries management approaches. The large vessels and the enthusiasm of vessel owners/skippers need to be particularly addressed when vessel quantity limit is considered to mitigate the problem of overfishing. [ABSTRACT FROM AUTHOR]

An amendment to this paper has been published and can be accessed via a link at the top of the paper. [ABSTRACT FROM AUTHOR]

Most renewable natural resources exhibit marked demographic and environmental stochasticities, which are exarcebated in management decisions by the uncertainty regarding the choice of an appropriate model to describe system dynamics. Moreover, demand and supply analysis often indicates the presence of instabilities and multiple equilibria, which may lead to management problems that are intensified by uncertainty on the evolution of the resource stock. In this paper the fishery management problem is used as an example to explore the potential of robust optimal control, where the objective is to choose a harvesting rule that will work under a range of admissible specifications for the stock-recruitment equation. The paper derives robust harvesting rules leading to a unique equilibrium, which could be helpful in the design of policy instruments such as robust quota systems. [ABSTRACT FROM AUTHOR]

This paper describes a non-traditional fisheries management concept and an indicator-based framework to encourage and guide management of invasive lionfish (Pterois spp.) fisheries in the temperate and tropical western Atlantic. We introduce the concept of optimum lionfish yield (OLY)—an extension of the concept of ecologically sustainable yield—which considers local ecological health in the establishment of fishery management targets. In contrast to traditional fishery targets, OLY is a target exceeding maximum sustainable yield (MSY) that still provides relatively high sustainable yield, but further contributes to population suppression beyond what is achievable through targets at or below MSY. Thus, OLY seeks to balance management trade-offs from both natural resource and invasive species management perspectives. In this study, we developed an age-structured population model and applied the concept of OLY to quantify targets to initiate management of a nationally-managed lionfish fishery in Belize. Socioeconomic and ecological data were used as indicators to formulate OLY values. The model indicates that lionfish in Belize are biologically robust to fishing pressure, which corroborates previous findings. Fishing lionfish at rates above MSY levels is expected to substantially reduce population abundance, much more so than fishing at rates below MSY levels, while having relatively minimal impacts on yield. Population suppression can be further enhanced by reducing size at selection, but this is expected to be done at a significant cost to landings. Together, these data support continued establishment of (managed) commercial lionfish fisheries throughout the invaded range to provide an alternative sustainable fishery resource and serve as a means of national- and international-level control. While the concept and framework described here is introduced for management of invasive lionfish, it could be applied to management of other invasive species, both aquatic and terrestrial. [ABSTRACT FROM AUTHOR]

In recent years, China has paid more and more attention to the development of marine economy and the management and protection of fishery resources. The management departments at all levels regulate and manage the fishing behavior of fishing vessels through the data of fishing trajectories. In this paper, the distribution of shrimp farms in the East China Sea is predicted by studying the trajectories and behavior patterns of shrimp boats in the system of fishing trajectories. At the same time, a set of shrimp farm distribution management system based on Back Propagation algorithm is established. It can monitor the trajectories of fishing boats and the distribution of shrimp groups in real time, which effectively improves the work efficiency and management mode of the management department. It also plays a positive role in regulating the behavior of fishing boats at sea. [ABSTRACT FROM AUTHOR]

The Persian Gulf Iranian fishery, just like many marine fisheries, needs sustainable management. The assessment of the sustainability of the fishery requires the development of a set of local indicators. This paper used an integrated multi-criteria participatory framework as a decision-making approach, to evaluate sustainability relating to ecological, economic, social, technological, and management dimensions. The indicators were modified from appropriate tools such as Rapfish and other reference studies. The determination of the importance of sustainability indicators was performed based on local stakeholders' opinions in the Persian Gulf, Iran. Three groups of stakeholders in this field have included fishers, managers, and researchers. Also, cognitive mapping as a soft methodology was applied to useful tools, for the assessment of the perceived linkage among indicators. The result of the assessment was analyzed and provided an overview for understanding the decision-making process and how to achieve sustainable fishery management in Iran. [ABSTRACT FROM AUTHOR]

In this paper, a new method based on the dual-frequency identification sonar imaging is presented to estimate the abundance of fish. The proposed method can detect, track and count fish individually. Fish targets can be acquired with a depth-first search algorithm once its edge is detected based on the Sobel Operator from a complicated image. Multiple fish targets can be tracked using the nearest neighbor algorithm combined with the Extended Kalman Filtering. In order to validate the effectiveness of the proposed method, an experiment was conducted in Qingcaosha reservoir in Shanghai. The manual detection method based on sonar images was used as a reference method. The results showed that the fish were identified with less than 5% error compared with the manual detection results. The statistical error of fish numbers between the automated method and the reference method was approximately 10%. [ABSTRACT FROM AUTHOR]

Technical and socio-economic characteristics are known to determine different types of fishers and their livelihood strategies. Faced with declining fish and water resources, small-scale fisheries engage into transformations in livelihood and fishing practices. The paper is an attempt to understand these changes and their socio-economic patterns, in the case of Singkarak Lake in West Sumatra, Indonesia. Based upon the hypothesis that riparian communities have diverse, complex yet structured and dynamic livelihood systems, the paper's main objective is to study, document and model the actual diversity in livelihood, practices and performance of inland small-scale fisheries along the Singkarak Lake, to picture how households are adapted to the situation, and propose an updated, workable model (typology) of those for policy. Principal component analysis and cluster analysis were used to develop a typology of fishing households. The results show that small-scale fishers can be classified into different types characterized by distinct livelihood strategies. Three household types are identified, namely 'farming fishers' households (type I, 30 %), 'fishing farmers' households (type II, 30 %), and 'mainly fishers' households (type III, 40 %). There are significant differences among these groups in the number of boats owned, annual fishing income, agriculture income and farming experience. Type I consists of farming fishers, well equipped, with high fishing costs and income, yet with the lowest return on fishing assets. They are also landowners with farming income, showing the lowest return on land capital. Type II includes poor fishing farmers, landowners with higher farming income; they show the highest return on land asset. They have less fishing equipment, costs and income. Type III (mainly fishers) consists of poorer, younger fishers, with highest return on fishing assets and on fishing costs. They have little land, low farming income, and diversified livelihood sources. The nature of their livelihood strategies is discussed for each identified group. This helps to understand the complexity and diversity of small-scale fishers, particularly in the study area which is still poorly known. This paper concludes with policy implication and possible management initiatives for environmentally prudent policy aiming at improvement of fishers' livelihood. [ABSTRACT FROM AUTHOR]

Most of the world's ocean fisheries are severely lacking in private property rights in the underlying natural resources or their close complements (e.g. harvesting volume). Therefore, according to standard property rights theory, these fisheries should be highly wasteful of potential economic rents from these resources. The question is whether this economic loss can be empirically verified and, if so, how large it is. This paper explains the concept and develops the analytical theory of economic and natural rents. Building on this and utilizing global fisheries data, the paper proceeds to estimate a global fisheries model, obtain numerical estimates of the rent loss in the world's ocean capture fisheries and provide reasonable confidence bounds for this loss. It is found that the global fisheries rent loss constitutes almost certainly a large fraction of the landed value of the global landings. The mean estimate of this loss is well over 50% of the value of landings. [ABSTRACT FROM AUTHOR]

Regulators in many countries have adopted individual quotas as a means of dealing with the open access problem inherent in fisheries. The Norwegian Purse Seine fishery has evolved over the last 40 years from an open access fishery to a Rights Based management system with individual vessel catch quotas assigned to all major fish species. Regulations do allow for merging vessel quota. The purpose of this paper is to employ an index approach to decompose vessel revenues and costs by factor components. The index approach can measure the importance of prices, output and regulatory changes impacting productivity and provides insight into changes in a mature IVQ fishery. The current study uses a large individual vessel data set for the period 1994–2013. Results show that over time output prices have been the main drivers associated with increased revenues. We correlate output prices with an evolving IVQ fishery, and changes in harvest and demand conditions. Ongoing capital investment, not offset by increased harvest, has seen productivity decline in the early periods of the study but some recovery towards the end of the period. [ABSTRACT FROM AUTHOR]

In this paper, we discuss the value of local knowledge of fishermen from Kigoma, along the North Eastern shores of Lake Tanganyika, regarding fish and climate-related issues of the lake. We explore how that knowledge can be incorporated into sustainable management activities. We used a qualitative approach to investigate the local knowledge and perception of changes and their causes. About 64 respondents comprising fishermen, fish processers, Beach Management Unit leaders, fisheries officers and elders were interviewed between April and December 2016. Our analysis shows that there have been increasing fishing activities in the lake from the 1970s. Increased fishing activities and climate-related changes in the lake have resulted in dramatic decreases in fish landings between the 1990s and the present. It was also revealed that fishermen hold valuable knowledge on fish availability, ecological conditions of the lake, and seasonal weather conditions. While they acknowledge the effects of changes in fishing practices and fishing pressure to explain the gradually decreasing fisheries, they have less understanding of the importance of longer-term changes in the lake environment resulting from climate change. This study concludes that future fisheries management could benefit from further incorporation of fishers' local knowledge such as those related to ecological conditions of the lake and pressures from fishing practices. By expanding mechanisms to include the fishermen's local knowledge, a strong signal is sent to them that their knowledge is valued by fisheries management. This has the potential to further motivate the fishermen to be active participants in contributing to sustainable management practices that can positively impact declining fish resources. In other words, fishermen need to be further "brought at the center" in decision-making processes that influence fisheries management options. [ABSTRACT FROM AUTHOR]

Participatory approaches to fisheries management are gaining increasing support from researchers, non-governmental organizations, and governments in Latin America, and different forms of participatory monitoring have been implemented over the last few decades. Among several advantages, these initiatives allow incorporation of fishers' knowledge on ecology, fishing practices, social aspects, markets, regulations, into different stages of management. In this paper, we analyze key features of participatory monitoring programs in small-scale coastal fisheries in South America (Argentina, Brazil, Chile and Uruguay) through a literature review complemented by expert opinion. Our review considered the fisheries and variables monitored; objectives, duration, institutional context of the monitoring programs; and factors that affect the extent of fishers' participation and the incorporation of fishers' knowledge. We found 14 case studies described in the literature, most of which correspond to benthic fisheries. Most cases focused on ecological and/or catch and effort variables; few initiatives included social variables. Initiatives were mainly driven by researchers in partnership with fishers and other stakeholders under formal or informal institutional arrangements. Institutional arrangements were largely responsible for the effectiveness of participation. In most cases, fishers' participation in monitoring was fostered as a component of a broader participatory co-management approach. Despite the challenges, participatory monitoring approaches are gaining traction in South America, receiving significant support from researchers in most cases, and from nongovernmental organizations in some cases. Increased governmental support for implementing and sustaining long-lasting participatory monitoring programs would strengthen monitoring initiatives that emerge locally. [ABSTRACT FROM AUTHOR]

Lake Naivasha fishery has been one of the most known sources of protein for most fringe communities in and around Naivasha. About 4000 livelihoods depend on the lake's fishery resource, both directly and indirectly, thus pose concerns on the future sustainability. The ultimate aim of this study was to explore efforts, costs and optimum levels of fishery exploitation in Lake Naivasha. The study relied on fish landings and fishing effort statistics recorded between 1980 and 2017 by Fisheries Department. Data was analyzed using Gordon Schaefer's model and excel operating software. A regression model was run to develop graphs that explained the relationship between total costs, total revenues, harvests and number of boats. Consequently to the main aim, the study sought to determine the total costs of fishing along with revenues generated. Findings show an increase in number of operational boats from twenty-six (26) in 1980 to fifty boats (50) in 2013. Thereafter, fishing boats increased significantly to one hundred and seventy-six (176) by 2017. Such a significant and unprecedented increase in efforts adversely affected natural fish stock and brooders of the major fish species in the fishery. Information in this paper will inform decisions on resource economics and management of fishing activities in Lake Naivasha, Kenya. [ABSTRACT FROM AUTHOR]

One of the central concerns of fisheries management is to understand the dynamics in the human-environment interactions especially in the context of the observed declining fish resources. This paper examines how agentic power drives the human-environment interactions. Drawing on interviews with fishers from Lake Tanganyika in Kigoma, Tanzania, the paper demonstrates how fishers negotiate their ways out of the structured rules and regulations to be able to access and benefit from the Lake's fish resources. Actors in the study areas maneuvered their way through the externally driven and established rules and regulations set to manage the fisheries. Thus, instead of actors being passive recipients of these external rules and regulations, they actively engage with them and challenge those that affect or contradict with community values and norms, which enable access to fish resources. It is therefore argued that actors are capable of negotiating their ways to access fish resources, even in the face of institutional structures that would otherwise impede these efforts. Their power to invent new possibilities to respond to problematic situations needs to be acknowledged by resource managers as they seek alternative approaches to future fishery management strategies. [ABSTRACT FROM AUTHOR]

Although fishing is regarded as a risky production process, limited attention has been given to the impact of input factor use on production risk. Production risk is particularly important for fisher behavior and fisheries management when input factors are restricted, since input restrictions can influence production risk in addition to output levels. This paper investigates production risk by estimating production and risk functions for the main vessel groups in the Norwegian fishing fleet. The results indicate that production risk is present and that the effect of input use on production risk varies between vessel groups. Capital has a risk-reducing effect in the ocean fleet, but are risk-increasing in coastal fisheries. Fuel use is found to be a risk-increasing input for most of the vessel groups, while labor use is risk-reducing. [ABSTRACT FROM AUTHOR]

The building of the ocean power strategy and the implementation of the blue agriculture plan urgently need to strengthen the sustainable development of marine fishery. Taking vulnerability as the starting point, this paper constructs the vulnerability index system of marine fishery industry ecosystem from the aspects of sensitivity and response capacity, and combines the entropy method with the Topsis to comprehensively analyze the spatio-temporal evolution characteristics of vulnerability of marine fishery industry ecosystem in the Bohai Rim Region from 2001 to 2015. The results show that: 1) In the time dimension, from 2001 to 2015, the vulnerability of the marine fishery industry ecosystem in the Bohai Rim Region shows a fluctuant and degressive trend; 2) In the spatial dimension, the spatial distribution of the marine fishery industry ecosystem vulnerability in the Bohai Rim Region presents the gradient characteristics which shows high vulnerability in the east and low vulnerability in the west. According to the evolution track of the system's vulnerability level, the vulnerability of the marine fishery industry ecosystem is divided into 'declining' and 'stable' types of evolutionary structures; 3) The development of marine fishery in the Bohai Rim Region needs to be derived from the marine fishery's ecological environment and the industrial development mode and structure, which can improve the marine environment remediation efforts, optimize the marine fishery industry structure, vigorously focus on pelagic fishery, and enhance the introduction of marine fishery's science and technology talents, etc. Then, the marine fishery's development in the Bohai Rim Region will be moving in the green, circular and sustainable direction. [ABSTRACT FROM AUTHOR]

In this paper I investigate the interaction of knowledge and institutions in the context of First Nations in the Pacific Northwest of Canada who have evolved management systems for fish and forest resources over hundreds of years. These management systems are viewed as institutions that are based on and apply knowledge systems over time. In the Nisga'a and Haida nations, knowledge systems guide management regimes that govern access, rights and responsibilities, harvesting, allocation of benefits and costs, technology, education and training. For the past hundred years these institutions and knowledge systems have come into conflict with knowledge and management systems imposed first by missionaries, settlers and colonizers and later from Provincial and National governments and corporations holding tenure rights assigned by those governments. National and international regimes such as the Law of the Seas and the Exclusive Economic Zones conflict with traditional institutions and knowledge systems by privileging one level of governance and consequently one form of knowledge and devaluing others. The paper is based on research conducted in the Pacific Northwest over the past eight years, primarily through interviews with elders, decision-makers, and resource users, as well as observation of cultural and resource practices. The research investigated the impacts of conflicting knowledge systems and the attempts to resolve those conflicts. The paper raises questions about knowledge systems and institutions, about institutional interplay, and the impact of international institutions on local institutions as they come into contact and conflict. [ABSTRACT FROM AUTHOR]